Dampers and couplings of this type are primarily used in large two-stroke and four-stroke diesel engines and gas engines for counteracting torsional vibrations in the power train. They may reach outer diameters of up to three meters.
Dampers and couplings of this type are known e.g. from DE 1 202 590 A or DE 30 33 302 A.
In order to provide defined damping properties the leaf spring assemblies have to be mounted very precisely between the intermediate pieces so as to correctly engage with the inner part. Further, their flexural behavior must be adapted to the desired purpose of application, which usually requires individual machining of the leaf springs. Usually, the leaf spring assemblies and the intermediate pieces are arranged on a flange and subsequently secured against each other by pressing or heat shrinking a clamping ring on the outer circumference of the leaf spring assemblies and of the intermediate pieces to create a clamping force in circumferential direction. Subsequently, this unit is fixed on the flange by means of screws connecting the intermediate pieces with the flange.
In this connection, DE 1 202 590 A suggests one or more inner rings between the clamping ring and the leaf spring assemblies and the intermediate pieces. The inner ring or rings have an axially tapered outer circumference engaging with a correspondingly tapered conical inner circumference of the clamping ring. Upon mounting the leaf springs assemblies and the intermediate pieces in the inner ring the outer clamping ring is placed on the outer circumference of the inner ring and pressed thereon axially by tensioning oppositely arranged flanges of the outer housing against each other via screws. These screws also secure the intermediate pieces on the outer housing and thus position the leaf spring assemblies and the intermediate pieces relative to the inner part.
The use of additional inner rings renders assembly of the damper or coupling complicated and laborious. Since the leaf spring assemblies and the intermediate pieces may slightly move relative to each other and further, as setting effects may occur, proper positioning of the leaf spring assemblies is difficult. In addition, setting of the intermediate pieces may reduce the overflow channels between the chambers and thus affect the damping properties.
As an alternative, DE 30 33 302 A suggests pressing a plurality of wedges between the leaf spring assemblies and the intermediate pieces, in which case the additional inner rings and a taper at the clamping ring can be avoided.
In both cases the leaf spring assemblies are clamped in circumferential direction, i.e. between substantially parallel side walls of the intermediate pieces to avoid reaction forces in radial direction.